That would be great to have integration with others authorities other than LetsEncrypt.
We do have enterprise customers that don't want to use Let's encrypt certificates and at the same time, don't want to create new automations with F5 XC.
You can still use certbot and integrate with them, for example https://docs.digicert.com/en/certcentral/certificate-tools/certificate-lifecycle-automation-guides/use-a-third-party-acme-client-for-host-automations/automation-examples-with-third-party-acme-clients.html
Also, a Venafi integration like is in place for F5 BigIP/BigIQ would support users of Venafi Cert Management Platform.